# include <stdio.h> 
void swap(int *x, int *y); 
void main() 
{ 
int i, j; 
i = 12; 
j = 36; 
printf("i and j before swapping: %d %d\n", i, j); 
swap(&i, &j);    
/* 传递变量i和j的地址 */ 
printf("i and j after swapping: %d %d\n", i, j); 
} 
void swap(int *x, int *y) 
{ 
int temp;     
temp = *x;    
*x = *y;      
*y = temp;    
} 
/* 存储变量x的值 */ 
/* 将 y 的值放入到x中 */ 
/* 将 x 的值放入到y中 */ 